Hurin and despair

[Lalaith]

There's been something troubling me ever since Lindil told me about the 'other' version of Hurin's end and the ruin of Doriath (in that the version in the Sil. is in fact Christopher and not JRR Tolkien.
In the professor's original, Hurin is not soothed by Melian when he comes with harsh words before Thingol's throne, but continues to rage around, causing indirect destruction to all around him and finally throwing himself into a river.
Now, I am no theologian but I'm pretty sure that despair is considered the worst of mortal sins and that Catholicism is especially hot on this point. To have Hurin die in mistaken pride and despair is then, according to Tolkien's beliefs, condemning him to damnation in the afterlife. This is worse even than the terrible death of Turin, who although he took his own life, had reached some kind of understanding of events before his death.
Considering Hurin's extraordinary loyalty, courage and steadfastness, this seems *very* hard and grim a conclusion.
Does anyone if there are any records of Tolkien's own thoughts on Hurin's end, and what literary function he was portraying? Or is the tale of Hurin perhaps an expression of Tolkien's bleakest and most pessimistic side?